Overall comments:
- Same disk I/O always blows--that's why RAID0 is retarded except for a VERY
SELECT FEW situations.
- Access time is FAR more important than sequential throughput on a boot
volume--that is why the Raptors are so good
- The T7K250 (I have one also) has NCQ whereas the Raptor does not
- The T7K250 also has a huge advantage in aerial density
- RAID0 often slows down a boot volume. Why? As array size grows, seeks get
slower, and seek time is the most important thing on a boot volume.
Greg
----- Original Message -----
From: "James Maki" <[EMAIL PROTECTED]>
To: "'The Hardware List'" <hardware@hardwaregroup.com>
Sent: Thursday, August 11, 2005 7:46 PM
Subject: [H] FW: Hard drive speeds
I did some unscientific tests this morning on hard drive file transfer
speeds. I simply used a stopwatch to time from selecting copy till the
copy
window closed. I found some of the results very interesting.
Hardware:
Motherboard: GIGABYTE GA-K8N Ultra-9 Socket 939 NVIDIA nForce4 Ultra
Both SATA RAIDs are connected via Nvidia SATA II RAID connectors
SATA I: Two 37GB WD Raptors (10,000 rpm) drives in RAID 0
SATA II: Two T7K250 250GB Hitachi SATA II w/ncq (7200 rpm) drives in RAID
0
ATA100: Seagate Barracude ATA with 8MB cache
File Size 355 MB 2575.5 MB
From To sec sec
SATA II SATA I 4.5 78.9 MB/s 36.5 70.6 MB/s
SATA I SATA II 5.8 61.2 MB/s 38.2 67.4 MB/s
SATA II ATA100 6.5 54.6 MB/s 41.6 61.9 MB/s
SATA I ATA100 6.5 54.6 MB/s 44.8 57.5 MB/s
ATA100 SATA II 8.0 44.4 MB/s 41.0 62.8 MB/s
ATA100 SATA I 8.5 41.8 MB/s 44.3 58.1 MB/s
Same disk transfers (partition to partition on same physical drive)
SATA I SATA I 13.5 26.3 MB/s 124.8 20.6 MB/s
SATA II SATA II 15.0 23.7 MB/s 110.5 23.3 MB/s
ATA100 ATA100 16.5 21.5 MB/s 119.4 21.6 MB/s
I thought the 10000rpm Raptors would be faster than the 7200 rpm Hitachi
drives with transfers to/from the ATA100 drive (the only "equal" starting
point I have). I was also surprised at how slow intra-drive transfers
were.
Now I have to re-think my "use the Raptors for the OS" philosophy. And at
the price of the a Raptor, you can purchase the 250 GB Hitachi. Seems like
a
no brainer -- 37 GB slower vs 250 GB faster? (in my defense, I purchased
the
Raptors almost 2 years ago, before SATA II was even available).
Just an FYI, but thoughts and comments always welcome.
Jim Maki
[EMAIL PROTECTED]
